(CNN) -- A nuclear weapons assembly and disassembly plant in Texas was on lockdown Friday morning because of a "potential security situation," according to a news release.

The Pantex Plant in Carson County, Texas, "has activated its Emergency Response Organization to respond to a potential security situation," the release said.

The event, which was not described, occurred around 8 a.m. the release said.

"The plant is in a lockdown status and the situation is being evaluated in order to facilitate security actions. Pantex employees are sheltered in place," it said.

Damien Lavera, a spokesman for the National Nuclear Security Administration, said Pantex is responding to a concern reported by an employee. Lavera said the plant management is in control of the situation, which he said should be resolved quickly.

Further details were not immediately available.

The Pantex plant is the nation's only nuclear weapons assembly and disassembly facility, the release said. The facility is managed and operated by B&W Pantex for the U.S. Department of Energy/National Nuclear Security Administration, according to the plant's Web site.